December 2009- It's large, powerful, heavily armored and ugly. But because it can save the lives of its riders, they don't mind one bit.

With their V-shaped hull deflecting the force of explosions beneath them, as well as their thick steel-plate outer shell, MRAPs protect U.S. soldiers against explosives and small-arms fire.

Navistar Defense, Warrenville, Ill., is one of the suppliers producing components for MRAP vehicles, which had to be manufactured rapidly and with high quality.

Inteva Products, Troy, Mich., a manufacturer of door systems, is a vendor for Navistar Defense that produces a new door-assist module for the Navistar Defense MaxxPro MRAP and heavier MaxxPro Plus and MaxxPro Dash models.

Inteva Products chose 3-Dimensional Services, Rochester Hills, Mich., to produce 63 components for the complex door-assist module, including the base plate, two latching components, door skin, hinges, side rods and slider blocks.

3-Dimensional Services specializes in design, engineering, production analysis, in-house tool construction, prototype parts and low- to medium-volume production runs.

Forming metal
An array of production processes were used to create these complex parts. Forming was used to produce the angle supports for the slide system; manual welding was used for the module's handles, levers and angle supports; and robotic welding was used for the main base plate and close-out brackets. Laser cutting and CNC machining processes were used on most of the module's metal components. Materials included A36 stainless, high-strength/low-alloy steel and CNC 1045 steel for the hinges.

"Our lasers [three- and five-axis] can cut through thick armor plate or slice through thin sheet metal, all with amazingly tight tolerances," noted Mike Brabandt, senior sales engineer at 3-Dimensional Services.

The three-axis laser cutting systems offer speed, accuracy and flexibility, and the five-axis systems can cut complex contours and shapes.

3-Dimensional has even produced proprietary laser systems in-house, including an ultrahigh-speed unit with cutting speeds up to 50,000 mm per minute.

Capabilities like these allowed the company to complete the prototype in seven days. Four design iterations followed, and all were successfully performed in one month because of the capabilities of the company's design and engineering department, which has more than 30 high-speed CAD terminals and employs nearly all major CAD/CAM packages.

The final design of the MRAP door module needed components to be zinc yellow chromate-plated for corrosion resistance so the module could be painted with a chemical agent-resistant coating.

3-Dimensional Services produced 300 to 400 modules per month for a total of 2,500 units.

"We know how important these modules and the vehicles they're a part of are for the safety of our troops, so we're gratified that we're able to work closely with Inteva to make this happen," remarked Brabandt. FFJ